Sunday, 17 February 2013

Jimi Photon Suzy-Q MKII

There was a bit hassle with this one, but now it's verified and working. Comments on the post are a good read if you're building this. Thanks to Mr. Photon for his amazing work, and special thanks to Pete who verified this.

Mind the notes about the transistors. This is drawn from schematic marked as revision G (The Maestro of Rock version).

More info from DIYSB-thread. Jimi's demo video:




78 comments:

  1. i am so honored to have one of my designs posted on this blog, it's one of the best resources for DIY guitar pedal builders on the planet!! thanks Miroslav and IvIark!
    this vero looks fantastic, thanks miro!!
    i will attempt to verify it this week for you, as the one i built is actually on three seperate vero circuit boards in the enclosure.
    this pedal and my toneblaster (tonebender variant, look for the mk 2.5 on diy or fsb) have pretty much replaced my bloated pedalboard live.
    i can get pretty much everything i need with these two pedals, a wah and an echo.. and the knobs on the guitar.
    it is INSANE, Nigel Tufnel loud..but there's a reason for it (a couple, actually)...the original design used vn2222 mosfets...they sound freaking great, but were very hissy, and very quiet. dimed, this was just below unity gain, so added a simple transitor boost my brother dino (digi2t) suggested at the end. that made it work! it had plenty of ball, unity gain was now about 2:00.
    but i played with the transitors, and decided to go with ge ac176's (npn) for q1 and 3, and keep the vn2222 mosfet in q2.
    that REALLY brought it to life!!
    on the DIYSB thread, Deafbutpicky found some tweaks/mods you may wanna look at, too.
    anyways.. again... i am deeply honored that i can make a humble contribution to the DIY guitar pedal freak community..
    miro, you not only rock, you on fire!!
    peace!

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    1. Love your videos; love your circuits; you're awesome, Jimi!

      If you are feeling charitable, can you recommend gain values for the NPN germanium trannies?

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    2. JIMI PHOTON>>>YOUR SOUND IS WONDERFUL> YOUR PLAYING IS GREAT< PLUS>>>YOU ARE A GREAT GUY> I"D BE PROUD TO TRY A NEW BOX FROM YOU>
      DICK WAGNER

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    3. agitprop (mikey!!) the two ge's values don't really matter, but fwiw, q1 was around 120 with 12ma leakage, and q3 i didn't even measure. i would advise to socket the transistors, and play with them til you're happy. it does NOT need germanium!! it sounds just as good with silicon. please socket and experiment so you can make it your own. ;)
      if ya want, next time we play if you wanna bring a flat blade screwdriver and remind me to bring my meter, we'll read the hfe for ya on the spot. cool? but please post 'em here so everybody else can benefit, too. peace!

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    4. Dick Wagner,
      man, you don't know what it means to me to have one of my life long heroes give me such kind words.. still hoping suzy can get you touring out here this year, so i can give you one of these in person.
      it's an honor and a pleasure to give you one of these, bro..
      i will get hammering on it this weekend, using miro's layout above. even got a nice magenta hammond box to put it in, no cheap ass metal radio shack box for you, my friend!!
      i am so so so honored to have you here. ;)
      guys, if you don't know dick wagner, you don't know DICK.
      google him. if it wasn't for dick, half the music we all grew up on, and most of the sounds we all love never would have happened!!
      so..
      i'm on it, maestro, and again, thanks!!
      namaste,
      jimi

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    5. I do, I just wasn't sure if it was THE Dick Wagner! Jimi you do bring the nicest guys to the blog! :o)

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    6. he's the real one, IvIark. there's only one maestro of rock, and he done visited your forum here. he's an awesome guy.
      i got the board miro worked up half populated last nite, gonna try and wrap it up tonite. rock on!

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    7. Holy f***, I get goosebumps just thinking about the guitar solo on "Slowburn" by Peter Gabriel.

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  2. WOW. That sounds Great. I really enjoy your contributions. The clip on the "Lardacious Phat Bastard" Pedal was very entertaining too. Keep Rockin and Contributing.

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    1. thanks jon, i am honored that IvIark and Miro have featured my stuff here... and an honor that good peeps like you like it.
      humbled, here!! ;)

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  3. Nice one Jimi, I could listen to your playing all day long, what amazing feel you have! Loved the LFB and this is definitely on my "to do list" as soon as I've debugged the f*** out of a couple my recent builds! You put me in a good "mood for a day"!! ( jesus, just shoot me)

    Thanks for your contribution, too :-)

    Mark, (not the main man)!

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    Replies
    1. mark, all good!! the amazing feel is just from a lifetime of playing the blues, often on some kind of psychedelic. lol.
      don't try this at home, i was a highly paid, trained proffessional!! ;)
      hey, if debugging, especially if you use tayda parts like we all do, make sure your resistors aren't "decapitated" internally...that has laid me low almost every time i have a problem, especially if the resistors are "standy uppy".
      peace!

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  4. Hey Jimi, where's the "stoopid pedal tricks" intro.
    Great demo as usual. Pyr0.

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    1. hi pyro,
      yah, i figure sometimes it's better to just let the damn pedal talk instead of my usual buffoonery.
      honestly, i was pretty stoned and just digging the fuck out of the sound of the pedal, so talking just wasn't necessary.
      some peeps bitch i babble too much, too, so... lol

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  5. fine playing jimi...you friggin rock

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    1. thank you maestro,
      without your example, i wouldn't be the guy i am today.
      i'd be a propellor beanie wearing upright bass player in a monkey suit. ;)
      again, honored, i mean HONORED that you stopped by.. this is an oasis of some fine circuits, if there's anything you see here you want, just say the word, bro.
      peace!!

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  6. This comment has been removed by the author.

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  7. miro,
    about 1/3rd of the way thru the build.
    i'll let ya know how it comes out.
    thanks again!
    also adding a link to this layout to the video page.
    rock on!
    pink

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    Replies
    1. No problem. Let's just hope i got it right :)
      +m

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  8. lololololol.... it looks right to me! like your style. nice and compact, but not TOO compact! ;)

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  9. found one mistake.... no power to q2. you need to eliminate the track cut at d 9. it still works, but not right. just caught this minor mistake... i think when i fix it, all will be well... back shortly.
    peace
    jimi

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  10. also, jumper from b 3 to d 3 needs to be eliminated i think.
    so far, the rest seems good.

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  11. ok, it's built, and running.
    that track cut at d9 needs to be removed, and the jumper from b3 to d3 needs to be removed.
    and then it works, and great. sounds just like my original, a little less noise (as to be expected)...beware!! them vn2222's blow out EASY...so don't forget to power down when trying different transistors!!
    fwiw, on this one, i ended up with mpsa13 in q1, ac176 in q2, and vn2222 in q3. bias trimpot about 1/2 way up. socket your transistors, and see what sounds best to you.
    on this build, the transistors are slightly different than on the original, but pretty much i think any npn's will work. you know you've got it when the attack and harmonic knobs are half way up, and the volume is about 9 o'clock. should be a little louder than unity, and sound like green river, or suzy q by creedence.
    i'll post voltages tomorrow, late for tonite's gig!!
    miro.. nice job on the vero!! undo them two little mistakes, and you can call it verified.
    thanks again!!
    peace out
    pink jimi

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  12. I built this on 2/19, had some questions, but pulled my post until my VN2222's arrived. It was built to the layout, works, but is very low. It does have a nice trebly edge to it, just not real loud (granted i am playing at a low volume, but other pedals do not behave like this. My original post posed the question of mixing CBE' with GGS's will this be explained in the next update? in the meantime, I will experiment. Not sure if the orientation is correctely displayed. One last question, I see the jumper at 3B-D, but do not see any cut at D9. Did you mean D19, as there are no cut on column 9. Thanks

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    1. i meant d 14, sorry, i was in a rush last nite.
      i will be back shortly with more detail..
      d being the 4th rail down from top, the track cut at dFOURTEEN needs to be eliminated or jumped. make sure you remove the jumper, b3 to d3, or q2 won't have b+, and will have q3 b tied to q2 c/d.
      that could explain why the volume is weak. this thing should be loud as hell... probably weak and trebley because q2 isn't recieving voltage until the corrections are made.
      all three transistors, from bottom to top would be e/b/c .
      you don't have to use mosfets... i'd socket and see what you like. fwiw, on the original one, i just stuck the mosfets in on a whim, cuz i'd been using them in fuzzfaces. so any npn transistors should work fine. germanium is not necessary even, tho it does make the fuzz a little warmer.
      i'll get ya voltages in a little bit...sorry for the confusion!

      the mosfets are insanely easy to blow out

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    2. ok, first, here's the corrected vero...hope ya don't mind, miro!

      http://i605.photobucket.com/albums/tt137/pinkjimiphoton/Jimi-Photon-Suzy-Q-MKII_zps1edebec9.png

      i went thru and took voltage readings. like i said, i tend to just stuff transistors in arbitrarily, until i like something.
      sometimes any old transistor will work. sometimes not.

      also.. think of all three transistor locations as being cbe, from top to bottom. i didn't lay this thing out originally as dsg or anything. ;)

      so anyways..

      voltages, with a fresh 9v alkaline : 9.66v

      q1, mpsa13 npn hfe unknown.. went higher than my meter reads.

      e 0.0
      b 1.18
      c 1.38

      q2, npn germanium, AC176 hfe: 140 @9ma leakage

      e 3.63
      b 3.71
      c 8.40

      q3, vn2222 n channel mosfet, hfe: 1,074

      e .10
      b 1.83
      c 1.87

      more deets here, if needed...

      http://www.diystompboxes.com/smfforum/index.php?topic=101178.0

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  13. Fixed the cut at D14. Removed the jumper at B3 to D3. Tried VN2222-Q1, OC71-Q2, MPSA13-Q3, waaay noisy. Tried a OC44 at Q2, still waaay noisy. Tried a 2N2907 at Q2, still noisy. Moved MPSA13 to Q1, VN2222 to Q3. way LESS noisy. BUT LOUD, even at zero on my Delta Blues 210, can't go above one on volume with Attack/Harmonics at noon, WAAAY LOUD!. the Trim Pot seemingly has no effect on Q1

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  14. it's supposed to be loud. unity gain is slightly below 9:00.
    it's an overdriver. you can turn the harmonics down all the way and just use it to wallop the hell out of the input of a tube amp. ;)
    you could probably drive a small speaker with it to an audible level, tho i haven't tried.
    yes, i agree, this seems to really be dependent on the transistors pete.
    could you please post voltages you've got?
    i revised this just slightly for mr. wagner, and added a really simple tone control. add a second wire to the wiper (center) of the 100k volume pot, and run that to the top (pin 3) of a 50k pot. take the wiper of that pot, and connect a .0047 (4.7n) cap from wiper to ground. you can even ground it to the back of the pot (if it's in the case already) or run a ground wire to the back of the pot with it, like on a guitar. that's it. will sweep between the full treble, and roll it off without muddying it up or whacking the midrange. simple but effective, and it's easily added or removed if you wanna check it out. i did a true bypass on it and couldn't tell when the tone control was in or out of the circuit unless it was turned down.

    you may also wanna add a small resistor from the ground pin of the attack control to ground... maybe 470r or 1k..then it won't turn all the way off, if you like to use the output for overdrive.

    mine i run the attack and harmonics about half way up, and the volume a shade below 9:00, and control tone and volume from my guitar. i've used it with strats firebirds les paul standard and les paul jr, even my tele and it seems to work about the same on all of 'em.
    i generally put it after my wah, with my toneblaster before the wah.

    thanks for building this! ;)
    peace
    jimi

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    1. Here is what I settled on (for now) and here are the respective voltages as oriented to the layout. (9.23v fresh battery)
      Q1-MPSA18, top-2.57, middle-0.62, bottom-0.0
      Trim Pot readings Q1 - 6.83 fully left, 3.38 middle, 2.58 fully right
      Q2-OC71, top-8.86, middle-8.81, bottom-3.11
      Q3-VN2222, top-1.70, middle-1.90, bottom-0.15
      IC1-LM741 with readings as follows
      1=0.00
      2=4.40
      3=4.19
      4=0.00
      5=0.00
      6=4.40
      7=8.85
      8=0.00
      Will add the Tone control and other suggested changes and report back

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    2. those voltages all look good to me!

      thanks pete!

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  15. here's updated schem

    [img]http://i605.photobucket.com/albums/tt137/pinkjimiphoton/SUZYQMKIIG_zps05fc2734.png[/img]

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  16. here's with the tone control:

    http://www.youtube.com/watch?v=evqTyXKRjSE

    unboxed, and turned pretty low, AND with a telecaster in front of the laptop with flourescent lights. sheesh.. so sorry about the hum

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    1. Sounds really sweet, my main guitar's a tele so it's always nice to try pedals which I know will work well.

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    2. I'll be revising the layout soonish. Thanks guys.
      +m

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    3. madferret, thanks man!!

      +miro... thank you, you do beautiful layouts!

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    4. Glad it turned out to be working after those two errors.

      Updated the layout and tagged it. Thanks to you all for your work! Jimi, Pete and Madferret!

      And sorry for the delay in correcting it, but i need to play some gigs and get wasted every now and then:D
      +m

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    5. getting wasted and playing gigs is more important bro, lol...gave us a chance to verify the layout, too!! ;)
      thanks for all YOUR work bro.. nice layout, and sounds great!
      peace!

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  17. miro,
    ya forgot to remove the jumper from b3 to d3!

    lol!!

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    1. He's still pissed Jimi :o)

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    2. oh man, i'm sorry, didn't mean to piss the man off!!
      ;)
      hell, i couldn't do a layout of this that good!! i didn't even try. ;)

      rock the f*ck on guys!!! ;)
      lol

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    3. No he's not. He had just terrible hangover yesterday.

      Hmm.. If that link is removed, there's not resistor going from gate to drain? That is still present on the rev.g of the schematic. So should the 1M resistor be omitted as well?
      +m

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    4. No, pissed as in drunk, not angry! :o)

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    5. Haha. Still a bit woozy, so i might not understand half of what's going on.. Seems like i ordered one black Mexican Telecaster last night :D But it was apparently pretty cheap. Used as a demo piece at the shop...

      So.. Once Jimi wakes up, i'd like to know about the fate of that 1M resistor...
      +m

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    6. Here is something to help decipher the intracacies of the language and conversation: http://www.effingpot.com/slang.shtml

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    7. Hahaha! My english as finnish, Mark's as british, and Jimi's as a american :) It's a small wonder how this thing doesn't happen more often :D
      +m

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    8. If you want some spanish english to add to the mess, I'm ready :P

      BR

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  18. and they call 'merkin english, too...
    lol..
    miro, i looked long and hard at the layout. i answered ya on the diysb thread too. i THINK that the jumper SHOULD be there to match the schematic, BUT only if there's a track cut at b4 so that b of q3 and g of q2 aren't connected.
    my eyes are bugging out more than my one lame wasted brain cell... the puss filled abyss between my deafened ears.. can handle. i THINK i'm right, but i'm toast, spent the day de-bugging a bad dsl installation. messy. boring. totally fucking baked. lol...
    incense and peppermints and patchouli kinda shit.
    ANYWAYS, here's the thing. i built this as per miro's original layout... had to jumper that one track cut, and remove that one jumper. but here's the thing...that means that the one i built had the 1m resistor exactly as pictured, which is a slightly different circuit.. i'll try and draw what it was. interesting change... sounded REALLY good to my jaded old ears. but it's already gone, off to dick.
    so miro, i may have to give you props too, the "mistake" if verifiable may well be revision h i guess.
    i played this thing thru my cyberdeluxe for about an hour before i shipped it today, tried it thru a variety of models and settings, and to me, it sounded great. so maybe that resistor being misplaced is a good thing.
    fuck.
    now i'm gonna have to build another one and put a switch on it to see which way sounds better.
    ;)
    hey pete, if ya feel adventurous, try temporarily jumping the jumper from b3 to d3, and cut the track at b4 and see if the noise you were having goes away... or else i gotta build another one, my girlfriend is ready to have my head at this point for taking over the dining room table. ;)

    miro.. damn, dude.. i don't know what to tell ya at this point!! ;)

    it seems to be ok as shown, without that jumper.

    i gotta get some sleep... check back tomorrow.
    we'll sort this thing out. ;)
    peace out guys

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  19. HMMMMMM.... this is what i built "by accident"..as shown on the vero minus the jumper from b3 to d3 and the cut at d14.
    slightly different beastie (i put in the transistors i used on dick's fuzz and voltages, but like i said, got an npn? plug it in, and see what ya like):

    http://i605.photobucket.com/albums/tt137/pinkjimiphoton/SUZYQMKIIH_zps138ff9b3.png

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  20. that should say cut at d14 jumpered. sorry. brain death.

    give props to miro for the "mod". i think it actually sounds a little warmer this way!

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  21. hang on, i am REALLY brain dead.
    i totally missed the track cut under that cap at b4, i am pretty sure i put it in the one i built.. ay yi yi..sorry..my bwain is widdle, and shouldn't be allowed out on it's own.
    miro, i can't answer your question yet... sorry man!! fuck! i shouldn't try to think. ;)

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  22. So I have the cut at B4 and I should re-install the B3-D3 jumper which connects D to G on Q2 through the 1M resistor. Having planned for just such a contingency when I removed the jumper, I replaced it with a socket. The jumper is back in its place. mucho better. meget bedre. Well Done mate! Might celebrate and get pissed. I don't think it is broke anymore, so we shouldn't try to fix it.

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  23. I also have the B50k Tone control installed (with 4.7n cap, just not sure I can hear any change. Did not install the suggested resistor, as this thing is loud and I would rather be able to back it off completely.

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  24. :D

    Now i'm pretty much confused the f* out. Don't know what i should fix and which way....
    +m

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    Replies
    1. Unverified tag back on, also i'll add "on-hold" and wait for final schematic before doing any more changes to the layout. :)
      +m

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  25. Mirosol,
    My build is exactly to the layout above with the exception of the transistors and add-ons. No more cut at D14. B3-D3 jumped as shown, and 1M resistor in place at B2-E2.
    Add-On:
    Tone control (B50k) added per Jimi instruction above, "revised this just slightly for mr. wagner, and added a really simple tone control, add second wire to the wiper (center) of the 100k volume pot, and run that to the top (pin 3) of a 50k pot. take the wiper of that pot, and connect a .0047 (4.7n) cap from wiper to ground." (Do not hear any difference.)
    Resistor @ Attack Control - I did NOT "add a small resistor from the ground pin of the attack control to ground... maybe 470r or 1k."

    While it is not my design and I defer to the designer and the schematician (is there such a word) for further tweaks and mods as deemed fit or appropriate, I think it is verified per the current vero with some clarification as follows. The only issue I would raise is the one I raised initially, with regards to referencing whether Q1, Q2 and Q3 are NPN, PNP, FET's or MOSFET's, that is to say, CBE or DGS, and what works best there.
    I have installed,
    Q1-MPSA18, CBE, top to bottom,
    Q2-OC71, CBE, top to bottom,
    Q3-VN2222, DGS, top to bottom,
    IC1-LM741

    I may go back and try per the 2N5089 and VN222 pair shown on original layout just for scheisse and griners.

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  26. lol...i'm on it guys. i can also verify that without the 1m resistor, it works too. ;)

    it SHOULD have it. that was the design. maybe the leakage in my q2 (ac 176 ) is letting it work. beats me.

    pete, any chance of a sound clip to hear?
    the "tone control" should only roll off the highs. it is pretty subtle.

    fuck. now i wish i hadn't sent the damn box out already. ;)

    i mean, it SOUNDS great! but... lol...

    there IS a new revision coming for the thing.. i will try and post it today miro.

    sorry about the hassle!!
    and thanks to pete for verification!

    oy.... lol

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    Replies
    1. Aaah. Don't worry. I just put the link back to the layout and post the fixed one :)

      Glad it got sorted! Thank you both!
      +m

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  27. thanks bro!
    fwiw, this is the last thing as i built it. i won't call it verified until i re-create it tho.
    http://i605.photobucket.com/albums/tt137/pinkjimiphoton/SUZYQMKiiiA_zpsaf58d2de.png build at your own risk for now!! this is as i built the last one, without the 1m resistor on q2.
    peace out!

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  28. As promised, I put a pair of VN2222's at Q1/Q2 and a 2N5089 at Q3. Works just fine, seems a little warmer/smoother, not so harsh. Having built a wheel of diodes from a 12 pole rotary switch (paired with the MXR Dist +), I am thinking of a switch that will select setup one or setup 2. Have to think about it awhile.
    Jimi - I will try to make a demo and post to SoundCloud, with the caveat that my playing sucks, and I cain't tipe neether (same fingers).

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  29. pete...
    i am so psyched!! awesome!!
    i bet you play fine!!

    we all kinda suck in our own way. in some cases, it makes us famous! ;)

    look forward to hearing it!!

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  30. Let me know if you can access this https://soundcloud.com/petevig/jimiphoton-suzy-q-mkii (again, my playing sucks)
    Quick explanation. There are three 3pdt toggle switches added to the build, centre lugs of each (2,5,8) are each connected to the sockets for Q1, Q2 and Q3, CBE or DGS respectively as you wish. To the outboard lugs I soldered six five hole three pin sockets to allow QC of various transistor types for "sparimentin". Current config (G) is VN2222 x 2 and 2N5089 on the top row of each in sequence Q123, and (H) MPSA18, OC71 and VN2222 on the bottom row of each in sequence.
    this link should get you to photobucket for some pics.
    http://i786.photobucket.com/albums/yy144/petevig/IMG_2085.jpg

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    1. thanks pete, you are godlyke my friend!
      sounds a lot like mine does, so i guess it's good! ;)
      you play fine.. you should hear some of the cat's i've hosted at open mics. ;)
      i am really psyched you built this, and thanks for verifying it for me!
      wow.. the difference in transistors is pretty amazing. the cleaner set sounds more like the way i try and set mine up.. but i like the raunch you're getting!! too cool! ;)

      love the pics, too!! thanks brother!!
      ;)

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    2. btw... guys... one of these should be in Mr. Wagner's hands tomorrow when his mail arrives. ;)

      hope he digs it! ;)

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  31. after hearing the differences with the switches for the transitors (and without that 1m resistor on q2 b&c...and with it) i think i'm gonna revise this just a little bit more to swap between si and ge on q2.

    also gonna try switching that resistor in and out, and see what kind of difference it makes. there's a bit of difference tonally between pete's, my initial build, and the one i built for dick.

    so.. like.. stay tuned.

    miro and IvIark... thank you!!
    pete...thank you for the independent verification!

    peace out

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  32. Glad I was able to contribute in some small way. Since I socketed the jumper, I may pull it and see what difference it makes. On another note, one more bit of food for thought for your consideration. With two sets of three transistors on the three 3PDT switches, there are two options of all down and all up, HOWEVER, there are four more options, namely DownUpUp, DownDownUP, UpDownDown, UpUpDown. I have tried this and find that the current mix of transistors are not necessarily playing well with those optional mixes, especially the OC71 (Germ). I will be experimenting with some other combos, using random selection and luck of the draw. Will post again if I find something noteworthy.

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  33. awesome pete. look forward to seeing what you come up with.
    i'm tinkering with a switch to put that 1m on q2 b and c in or out of the circuit.
    also thinking about using a 3pdt toggle to switch between the ge and some other transistor on q2 as well.
    i mean basically, this is a buffer into the harmonic clipper adaptation we came up with, with a simple booster at the end.
    different single opamps with better specs, maybe even "stacked" may be interesting.. but i don't think this really needs to be louder. ;)
    q1 and 2 are the kustomish part. and q3, pick your transistor.
    i have learned the hard way, to make sure you power down when swapping stuff.
    also learned the hard way *hah! hard, he said hard, beavis... heh heh...*
    that i don't trust pinouts OR hfe's. it always seems to work out different. at least to me.
    our old friend devi ever does that too. sometimes, a transistor just SOUNDS better backwards. i know that's wrong, but hey, if it sounds good, it IS good.
    socket. try a bunch of different trannies, including ones you wouldn't expect to work.
    if you don't mind blowing stuff up once in a while, you can find some really cool stuff.
    pete, your idea of the switches was awesome. and i love the box. ;)
    very interested to know how it sounds un-jumpered. wondering if that's why dick's sounded a little warmer and darker.. also wondering if that's why your tone control wasn't working. it doesn't sweep the tone, it just cuts the high end..it sweeps right down into some high midrange frequency, it should sound kinda dull all the way down and like it's not there all the way up.
    anyways...thanks to all of you again!! rock on!
    peace,
    jimi

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  34. Here is my update.
    Row 1 switches,
    Q1=MPSA12
    Q2=VN2222
    Q3=BS170 (pinout is reversed from layout)
    Row 2 Switches,
    Q1=MPSA18
    Q2=OC71
    Q3=VN2222
    This arrangement keeps the lower gain on the bottom switch selections and high gain on top. It also allows alternating switch combinations without getting that squishy sound or causing sound to cut out with aggressive picking.
    Its late and I can't turn the volume up until tomorrow. Hopefully it holds try at higher volumes and pot rotation, as the volume is set a 7, and H & F at noon.

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  35. pete,
    did you pull that jumper and try it?

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  36. the MAN likes it. i am like,, beyond psyched..
    thanks dick!
    and thanks to all of you guys..
    peace out..
    jimi

    http://i605.photobucket.com/albums/tt137/pinkjimiphoton/likesit_zps2baebe10.png

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    Replies
    1. Excellent stuff, congrats Jimi! :o)

      Delete
  37. jimi,
    pulled the jumper, no workie on Row 1 setup, dead, dead, dead, nada, zip, zilch, even at full up volume.
    on the other hand, Row 2 setup works fine without the jumper, however there is absolutely no change in tone, volume or distortion that I noticed. Please note that I did not crank it up as my short experience with this circuit has quickly taught me otherwise.
    I did not try mixing the switch settings, on the premise that it was likely a waste of time.

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  38. thanks pete,
    wow, that's weird!!
    thanks for the headsup.
    ;)

    cool, the resistor stays. ;)
    peace!

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  39. Hello folks!

    I'm having problems sourcing the LM741, can I use a TL071 here instead?
    Pinout is the same, not sure about other characteristics...

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    Replies
    1. Yeah should work fine! Try it. There's no harm in experimenting.

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    2. yep. any single opamp will probably do the trick, the tl071 is probably a lot quieter. i just used the 741 cuz it was handy, it's not a "mojo" part.
      good luck goran!
      peace!
      pjp

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  40. quick revision:

    if the harmonics knob oscillates, add a 1k resistor to the high side of the pot, and a 220r resistor to the wiper, should cure it.

    if you want the tone control, as dick wagner did, it's stupid simple.

    run a wire from the wiper of the volume pot to the high side of a 50 k pot.
    run a .039u cap to ground from the wiper of the tone pot.

    done deal. will let you sweep a good bit of tone without being real lossy.

    yes, i tried more traditional tone controls, this was simpler and worked better. you can ground the cap right to the case of the tone pot (as i do) if you want.

    anyways.. onwards n upwards
    pjp

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  41. also... discovered my fav transistor combo is ne5534 for the chip, ac176 for the q1, and a darlington like mpsa18 for the last stage. gives it a nice crunch

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